Project update

I've been working pretty hard on my project for the last few weeks. I had a few problems and a few set-backs, but I've discovered something really key today (the porosity of an intraluminal thrombus in an abdominal aortic aneurysm is 0.91 by the way).

The good news about that is that I've now had enough courage to update my Gantt chart, which is now somewhat improved on the last time I did it. I'm still behind schedule, but key thing... I'm not *as* far behind schedule as I was .... AND.... I know what I'm doing tomorrow and Tuesday more-or-less, so hopefully I'll catch up some more by mid-week.

Sometimes I get frustrated by fortran!

I like FORTRAN. Really I do. I like creating programs that work and give me answers that mean things and that I can use to help me write reports and things for uni.

I have problems with it though. It took me ages to understand what I'm trying to do with my latest program. Creating a fortran program based on misunderstandings is never a good idea. I now have the concept though. I understand roughly what I'm trying to do.

The only thing is that now I know what I'm doing I can't figure out how to tell the computer the right fortran so that it will give me the desired answers.

My summer project

My project title is:
"Species (MMP) transport in an abdominal aortic aneurysm with a porous ILT."

A quick vocab guide might be of use to those who do not have a clue what that means...
MMPs are Matrix-metalloproteinases. I'm not entirely sure what they are, but I have a feeling they're tricky buggers.
An aneurysm is when your artery swells up like a balloon due to a problem in the artery wall (usually thinning caused either by age or by an accident). The aorta is the main artery going from your heart up and round and then down towards your legs. Aneurysms may rupture and when they do the chances of survival are not good. Abdominal aortic aneurysms are known as AAAs or Triple-As.
ILT is an Intraluminal Thrombus. A thrombus is a blood clot. Intraluminal means it's within a structure (so within the artery).
Hemodynamics is the study of the flow of blood.

Overall agreed objectives:

Write a medical review of AAAs including MMP influence.

Write a scientific review of AAAs including hemodynamics, experimental and computer models.

Develop a simple steady flow model of a AAA with a porous thrombus and mass transport.

Develop a simple pulsatile flow model of a AAA with a porous thrombus and mass transport.

Mesh a realistic model taken from segmented CT images.

Incorporate the simplified anatomical model developed above into the realistic anatomical model.

Analysis of interactions between the thrombus, blood, and the artery wall with respect to AAA progression.

Deliverable(s):
1. A simple CFD model of AAA mass transport in steady flow with a porous ILT.
2. A simple CFD model of AAA mass transport in pulsatile flow with a porous ILT.
3. A realistic model of AAA mass trans port in pulsatile flow with a porous ILT.
4. A project report

I'll be using ANSYS FLUENT to model the aneurysm in 2D and 3D. The 3D version will come from a CT scan from a real-live poorly person. I hope that they got patched up okay and are still alive.

I expect to be very busy this summer. The project is due to start at the beginning of June. Before then I am going to have to do some medical reading. I'm really excited about this project. It sounds really cool (and hard work) and interesting.

Progress in CFX

Last term we did an introductory course for ANSYS CFX and I found it really interesting. ANSYS CFX is a computer package with which you can design an object, then create a mesh to cover it (imagine a spider's web stretched over the object) and then you can set parameters and things and tell it to model what would happen if water came in one end, air through the top and there was just one outlet pipe (for example). Then as if by magic the program thinks about it for a while and gives you an answer.

Well now we have to do some coursework using it, it's not due until May and today I started it finally. I've been trying to start it for the past 4 weeks now, but all my attempts have been thwarted by the problem of a locked door. There is just one room in the whole university that has CFX computers in apparently and as CFD Masters students we are allowed to go in there. Only the door is always locked. It took two weeks to ascertain who was going to be allowed to give us permission to go in there. Then that person was off sick, then he was in meetings for most of last week. Well today I caught up with his secretary again and found out that the room is meant to be unlocked in office hours and that we can go in whenever we want, so long as there isn't a class in progress. Hurrah!

So I spent an hour or so playing with a piece of software I learnt a little bit about 3 months ago and haven't been able to touch since. On my third attempt I managed to complete the basic design for the object we were told to create. I meshed it first time without any problems. Then I tried to open it in what they call the Pre-Processor. I failed. It's got the wrong file extension and I have no idea how to convert it to the correct one. I can't recall that we were ever told how to go from meshing to pre. This is frustrating. I'm hoping that someone else in my class knows and can show me later in the week. This should not be a problem considering we're now allowed in the room Mon-Fri, 9am-5pm.

Masters Summer Project

I have to choose a project to do for my Masters in CFD over the summer this year. We've not been given the list of titles yet, but I've been thinking about the kind of thing I'd like to do. I'm really into bubbles and I also like two-phase/multi-phase flow. So I'd like to do something along those lines as it would be interesting for me. Hopefully it will also be useful for me in the future too. That depends on what I do in the future though.

So the summer project. In an email from one of the professors the other day is one of the proposed titles. "CFD Simulation of Droplet Formation in Membrane Emulsification."

The word "droplet" caught my eye straight away as that fits into the whole multi-phase flow idea that I like. Plus a droplet of liquid in air is the opposite of a bubble really, if you think about it. So I googled for "Membrane Emulsification" and got this website. That has a really simple diagram showing something that I assume would be a similar sort of set up to what they would like the student to model for the project.

How amazing is that? I think it's fascinating!